Assessment of aerosol absorption measurements
Authors
Allison C. McComiskey — Brookhaven National Laboratory
Anne Jefferson — NOAA- Earth System Research Laboratory
Manvendra K. Dubey — Los Alamos National Laboratory
Allison C Aiken — Los Alamos National Laboratory
Jerome D Fast — Pacific Northwest National Laboratory
Connor J. Flynn — University of Oklahoma
Evgueni Kassianov — Pacific Northwest National Laboratory
Graham Feingold — Earth System Research Laboratory
Category
Absorbing Aerosol
Description
The absorbing component of aerosol is second only to aerosol amount (optical depth) in importance for calculating aerosol radiative forcing. Aerosol optical depth is measured with reasonable accuracy over the globe from ground and space, but measurements of absorption from all platforms remain highly uncertain. Estimates of absorption from space depend on aerosol typing, ground-based remote sensing retrievals require many assumptions, and various approaches to in situ measurements each have positive and negative attributes. Concerns have recently been raised that aerosol chemistry may bias in situ measurements made from filter-based approaches. ARM has been making redundant measurements of the aerosol absorption coefficient in situ at the surface for several years at the Southern Great Plains. Collocated remote sensing instruments are employed with both established and newly developed retrievals of the absorbing component of aerosol. Together with new chemistry measurements, this inclusive dataset is used to assess the differences among various approaches to determining aerosol absorption, causes for these differences, and the implications of their uncertainties for calculating radiative forcing. An analysis of this data from July through December 2011 is presented.Lead PI
Graham Feingold — Earth System Research Laboratory